Home

Cluster A personality disorders

Cluster A personality disorders are characterised by odd and eccentric behaviours. Poor social functioning is prominent, with people experiencing significant difficulties in relating to others and maintaining relationships.

Article by Katie Loader

First published: Last updated:
Expand all
Collapse all
Definition

The term personality disorder refers to a set pattern of characteristics and maladaptive behaviours that cause people to think, feel and relate to others in ways that are not in keeping with social norms (World Health Organization, 2019). The International Classification of Diseases (ICD-10) lists 10 types of personality disorders which are commonly grouped into clusters – A, B and C – depending on their shared characteristics and aetiology.

Cluster A personality disorders include:

paranoid personality disorder
schizoid personality disorder
schizotypal personality disorder

These personality disorders are characterised by odd and eccentric behaviours. Poor social functioning is prominent, with people experiencing significant difficulties in relating to others and maintaining relationships. There is a 3.8% global prevalence of cluster A personality disorders (Winsper et al, 2019), with schizoid personality disorder being the most common and paranoid personality disorder the least. All three tend to be more common

To view the rest of this content login below or request a demo

Log in
Symptoms

The symptoms of paranoid personality disorder include:

  • suspiciousness and mistrust
  • lack of forgiveness
  • extreme sensitivity to setbacks
  • misinterpretation of others’ actions as hostile or disrespectful
  • recurrent suspicions about fidelity in relationships
  • combative behaviour
  • excessive sense of self-importance (Lee, 2017)

People with paranoid personality disorder tend to be hypersensitive and hypervigilant. They are often fearful and anxious that they will be mistreated and view other people as deceitful. This fear can often manifest as aggressive and hostile behaviour. People with this personality disorder often hold concrete views, have difficulties viewing other perspectives and significantly struggle with close relationships (Lee, 2017).

The symptoms of schizoid personality disorder include:

  • social withdrawal
  • isolation
  • preference for solitary activity
  • limited capacity to express feelings
  • limited capacity for joy (Li, 2021)

People with schizoid personality disorder are viewed as reclusive. They tend to choose lifestyles and jobs that limit social interactions and are indifferent towards other people’s

To view the rest of this content login below or request a demo

Log in
Aetiology

Symptoms of cluster A personality disorders are similar to those of psychotic disorders, but are not as intense and do not impact as much on functioning. The onset and course of symptoms are in line with other personality disorders (World Health Organization, 2019). There are several shared risk factors between the three presentations:

Genetics

Both schizoid and schizotypal personality disorders share genetic links to schizophrenia; schizotypal is additionally linked to bipolar affective disorder (Ma et al, 2016). Paranoid personality disorder is associated with depressive and delusional disorders (Ma et al, 2016). Genetic factors are linked to the more stable symptoms of cluster A personality disorders, whereas the transient symptoms are influenced by environmental factors (Kirchner et al, 2018).

Neurochemical

Variable dopamine levels have been found in cluster A personality disorders, which can account for certain symptoms such as paranoia (Lee, 2017). Gamma-aminobutyric acid (GABA), a neurochemical

To view the rest of this content login below or request a demo

Log in
Diagnosis

Diagnosis is based on the clinical symptoms. Several tools can support diagnosis, none of which are superior to the other (Kirchner et al, 2018). A detailed assessment is vital to understand the severity and impact of symptoms and associated risks, as well as to evaluate the possible differential diagnoses and comorbidities (Kirchner et al, 2018).

Suicide risk in people with paranoid and schizoid personality disorders is inadequately researched. Comorbid psychiatric conditions, poor communication skills and lack of close relationships can increase suicide risk (Lee, 2017). Schizotypal personality disorder alone is associated with increased suicide risk (Sher, 2021). Earlier onset and more depressive symptoms can increase risk, but this can be reduced by accurate diagnosis and suitable treatment (Sher, 2021).

Cluster A personality disorders are highly comorbid with other personality disorder subtypes. Paranoid personality disorder is commonly diagnosed alongside emotionally unstable personality disorder

To view the rest of this content login below or request a demo

Log in
Management

Treatments for cluster A personality disorders are poorly researched; there are no current UK guidelines or licenced medications for the management and treatment of these disorders. Additionally, people with cluster A presentations do not readily seek treatment or participate in research, given their symptoms of paranoia and social difficulties.

Paranoid personality disorder

Koch et al (2016) found no evidence of any suitable pharmacological treatment in their review, but advised clinicians to treat emergent symptoms as required. A review by Lee (2017) found that a cognitive behavioural therapy approach could help to ease feelings of suspiciousness and mistrust, but there is no evidence base to support this. Lack of research and poor treatment outcomes are commonly attributed to their extreme mistrust of others, including clinicians.

Schizoid personality disorder

Again, Koch et al (2016) found no evidence for any suitable pharmacological treatment for schizoid personality disorder. Li (2021)

To view the rest of this content login below or request a demo

Log in
NMC proficiencies

Nursing and Midwifery Council: standards of proficiency for registered nurses 

Part 1: Procedures for assessing people’s needs for person-centred care 

1. Use evidence-based, best practice approaches to take a history, observe, recognise and accurately assess people of all ages

Part 2: Procedures for the planning, provision and management of person-centred nursing care

3. Use evidence-based, best practice approaches for meeting needs for care and support with rest, sleep, comfort and the maintenance of dignity, accurately assessing the person’s capacity for independence and self-care and initiating appropriate interventions

11. Procedural competencies required for best practice, evidence-based medicines administration and optimisation

To view the rest of this content login below or request a demo

Log in
Resources

Esterberg ML, Goulding SM, Walker EF. Cluster A personality disorders: schizotypal, schizoid and paranoid personality disorders in childhood and adolescence. J Psychopathol Behav Assess. 2010;32(4):515–528. https://doi.org/10.1007/s10862-010-9183-8 

Hemmati A, Rezaei F, Rahmani K et al. Differential profile of three overlap psychiatric diagnoses using temperament and character model: a systematic review and meta-analysis of avoidant personality disorder, schizoid personality disorder, and social anxiety disorder. Annals of Indian Psychiatry. 2022;6(1): 15–26. https://doi.org/10.4103/aip.aip_148_21 

Kirchner SK, Roeh A, Nolden J, Hasan A. Diagnosis and treatment of schizotypal personality disorder: evidence from a systematic review. NPJ Schizophr. 2018;4(1):20. https://doi.org/10.1038/s41537-018-0062-8 

Koch J, Modesitt T, Palmer M et al. Review of pharmacologic treatment in cluster A personality disorders. Ment Health Clin. 2016;6(2):75–81. https://doi.org/10.9740/mhc.2016.03.75 

Lee R. Mistrustful and misunderstood: a review of paranoid personality disorder. Curr Behav Neurosci Rep. 2017;4(2):151–165. https://doi.org/10.1007/s40473-017-0116-7 

Li T. An overview of schizoid personality disorder. Advances in Social Science, Education and Humanities Research. 2021;615:1657–1663. https://doi.org/10.2991/assehr.k.211220.280 

To view the rest of this content login below or request a demo

Log in